drivers/misc/mei/amthif.c

   1 /*
   2  *
   3  * Intel Management Engine Interface (Intel MEI) Linux driver
   4  * Copyright (c) 2003-2012, Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/fs.h>
  19 #include <linux/errno.h>
  20 #include <linux/types.h>
  21 #include <linux/fcntl.h>
  22 #include <linux/aio.h>
  23 #include <linux/ioctl.h>
  24 #include <linux/cdev.h>
  25 #include <linux/list.h>
  26 #include <linux/delay.h>
  27 #include <linux/sched.h>
  28 #include <linux/uuid.h>
  29 #include <linux/jiffies.h>
  30 #include <linux/uaccess.h>
  31 #include <linux/slab.h>
  32
  33 #include <linux/mei.h>
  34
  35 #include "mei_dev.h"
  36 #include "hbm.h"
  37 #include "client.h"
  38
  39 const uuid_le mei_amthif_guid  = UUID_LE(0x12f80028, 0xb4b7, 0x4b2d,
  40                                          0xac, 0xa8, 0x46, 0xe0,
  41                                          0xff, 0x65, 0x81, 0x4c);
  42
  43 /**
  44  * mei_amthif_reset_params - initializes mei device iamthif
  45  *
  46  * @dev: the device structure
  47  */
  48 void mei_amthif_reset_params(struct mei_device *dev)
  49 {
  50         /* reset iamthif parameters. */
  51         dev->iamthif_current_cb = NULL;
  52         dev->iamthif_msg_buf_size = 0;
  53         dev->iamthif_msg_buf_index = 0;
  54         dev->iamthif_canceled = false;
  55         dev->iamthif_ioctl = false;
  56         dev->iamthif_state = MEI_IAMTHIF_IDLE;
  57         dev->iamthif_timer = 0;
  58         dev->iamthif_stall_timer = 0;
  59         dev->iamthif_open_count = 0;
  60 }
  61
  62 /**
  63  * mei_amthif_host_init - mei initialization amthif client.
  64  *
  65  * @dev: the device structure
  66  *
  67  * Return: 0 on success, <0 on failure.
  68  */
  69 int mei_amthif_host_init(struct mei_device *dev)
  70 {
  71         struct mei_cl *cl = &dev->iamthif_cl;
  72         struct mei_me_client *me_cl;
  73         unsigned char *msg_buf;
  74         int ret;
  75
  76         dev->iamthif_state = MEI_IAMTHIF_IDLE;
  77
  78         mei_cl_init(cl, dev);
  79
  80         me_cl = mei_me_cl_by_uuid(dev, &mei_amthif_guid);
  81         if (!me_cl) {
  82                 dev_info(dev->dev, "amthif: failed to find the client");
  83                 return -ENOTTY;
  84         }
  85
  86         cl->me_client_id = me_cl->client_id;
  87         cl->cl_uuid = me_cl->props.protocol_name;
  88
  89         /* Assign iamthif_mtu to the value received from ME  */
  90
  91         dev->iamthif_mtu = me_cl->props.max_msg_length;
  92         dev_dbg(dev->dev, "IAMTHIF_MTU = %d\n", dev->iamthif_mtu);
  93
  94         kfree(dev->iamthif_msg_buf);
  95         dev->iamthif_msg_buf = NULL;
  96
  97         /* allocate storage for ME message buffer */
  98         msg_buf = kcalloc(dev->iamthif_mtu,
  99                         sizeof(unsigned char), GFP_KERNEL);
 100         if (!msg_buf) {
 101                 ret = -ENOMEM;
 102                 goto out;
 103         }
 104
 105         dev->iamthif_msg_buf = msg_buf;
 106
 107         ret = mei_cl_link(cl, MEI_IAMTHIF_HOST_CLIENT_ID);
 108         if (ret < 0) {
 109                 dev_err(dev->dev, "amthif: failed cl_link %d\n", ret);
 110                 goto out;
 111         }
 112
 113         ret = mei_cl_connect(cl, NULL);
 114
 115         dev->iamthif_state = MEI_IAMTHIF_IDLE;
 116
 117 out:
 118         mei_me_cl_put(me_cl);
 119         return ret;
 120 }
 121
 122 /**
 123  * mei_amthif_find_read_list_entry - finds a amthilist entry for current file
 124  *
 125  * @dev: the device structure
 126  * @file: pointer to file object
 127  *
 128  * Return:   returned a list entry on success, NULL on failure.
 129  */
 130 struct mei_cl_cb *mei_amthif_find_read_list_entry(struct mei_device *dev,
 131                                                 struct file *file)
 132 {
 133         struct mei_cl_cb *cb;
 134
 135         list_for_each_entry(cb, &dev->amthif_rd_complete_list.list, list)
 136                 if (cb->file_object == file)
 137                         return cb;
 138         return NULL;
 139 }
 140
 141
 142 /**
 143  * mei_amthif_read - read data from AMTHIF client
 144  *
 145  * @dev: the device structure
 146  * @file: pointer to file object
 147  * @ubuf: pointer to user data in user space
 148  * @length: data length to read
 149  * @offset: data read offset
 150  *
 151  * Locking: called under "dev->device_lock" lock
 152  *
 153  * Return:
 154  *  returned data length on success,
 155  *  zero if no data to read,
 156  *  negative on failure.
 157  */
 158 int mei_amthif_read(struct mei_device *dev, struct file *file,
 159                char __user *ubuf, size_t length, loff_t *offset)
 160 {
 161         struct mei_cl *cl = file->private_data;
 162         struct mei_cl_cb *cb;
 163         unsigned long timeout;
 164         int rets;
 165         int wait_ret;
 166
 167         /* Only possible if we are in timeout */
 168         if (!cl) {
 169                 dev_err(dev->dev, "bad file ext.\n");
 170                 return -ETIME;
 171         }
 172
 173         dev_dbg(dev->dev, "checking amthif data\n");
 174         cb = mei_amthif_find_read_list_entry(dev, file);
 175
 176         /* Check for if we can block or not*/
 177         if (cb == NULL && file->f_flags & O_NONBLOCK)
 178                 return -EAGAIN;
 179
 180
 181         dev_dbg(dev->dev, "waiting for amthif data\n");
 182         while (cb == NULL) {
 183                 /* unlock the Mutex */
 184                 mutex_unlock(&dev->device_lock);
 185
 186                 wait_ret = wait_event_interruptible(dev->iamthif_cl.wait,
 187                         (cb = mei_amthif_find_read_list_entry(dev, file)));
 188
 189                 /* Locking again the Mutex */
 190                 mutex_lock(&dev->device_lock);
 191
 192                 if (wait_ret)
 193                         return -ERESTARTSYS;
 194
 195                 dev_dbg(dev->dev, "woke up from sleep\n");
 196         }
 197
 198
 199         dev_dbg(dev->dev, "Got amthif data\n");
 200         dev->iamthif_timer = 0;
 201
 202         if (cb) {
 203                 timeout = cb->read_time +
 204                         mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
 205                 dev_dbg(dev->dev, "amthif timeout = %lud\n",
 206                                 timeout);
 207
 208                 if  (time_after(jiffies, timeout)) {
 209                         dev_dbg(dev->dev, "amthif Time out\n");
 210                         /* 15 sec for the message has expired */
 211                         list_del(&cb->list);
 212                         rets = -ETIME;
 213                         goto free;
 214                 }
 215         }
 216         /* if the whole message will fit remove it from the list */
 217         if (cb->buf_idx >= *offset && length >= (cb->buf_idx - *offset))
 218                 list_del(&cb->list);
 219         else if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
 220                 /* end of the message has been reached */
 221                 list_del(&cb->list);
 222                 rets = 0;
 223                 goto free;
 224         }
 225                 /* else means that not full buffer will be read and do not
 226                  * remove message from deletion list
 227                  */
 228
 229         dev_dbg(dev->dev, "amthif cb->response_buffer size - %d\n",
 230             cb->response_buffer.size);
 231         dev_dbg(dev->dev, "amthif cb->buf_idx - %lu\n", cb->buf_idx);
 232
 233         /* length is being truncated to PAGE_SIZE, however,
 234          * the buf_idx may point beyond */
 235         length = min_t(size_t, length, (cb->buf_idx - *offset));
 236
 237         if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length)) {
 238                 dev_dbg(dev->dev, "failed to copy data to userland\n");
 239                 rets = -EFAULT;
 240         } else {
 241                 rets = length;
 242                 if ((*offset + length) < cb->buf_idx) {
 243                         *offset += length;
 244                         goto out;
 245                 }
 246         }
 247 free:
 248         dev_dbg(dev->dev, "free amthif cb memory.\n");
 249         *offset = 0;
 250         mei_io_cb_free(cb);
 251 out:
 252         return rets;
 253 }
 254
 255 /**
 256  * mei_amthif_send_cmd - send amthif command to the ME
 257  *
 258  * @dev: the device structure
 259  * @cb: mei call back struct
 260  *
 261  * Return: 0 on success, <0 on failure.
 262  *
 263  */
 264 static int mei_amthif_send_cmd(struct mei_device *dev, struct mei_cl_cb *cb)
 265 {
 266         struct mei_msg_hdr mei_hdr;
 267         struct mei_cl *cl;
 268         int ret;
 269
 270         if (!dev || !cb)
 271                 return -ENODEV;
 272
 273         dev_dbg(dev->dev, "write data to amthif client.\n");
 274
 275         dev->iamthif_state = MEI_IAMTHIF_WRITING;
 276         dev->iamthif_current_cb = cb;
 277         dev->iamthif_file_object = cb->file_object;
 278         dev->iamthif_canceled = false;
 279         dev->iamthif_ioctl = true;
 280         dev->iamthif_msg_buf_size = cb->request_buffer.size;
 281         memcpy(dev->iamthif_msg_buf, cb->request_buffer.data,
 282                cb->request_buffer.size);
 283         cl = &dev->iamthif_cl;
 284
 285         ret = mei_cl_flow_ctrl_creds(cl);
 286         if (ret < 0)
 287                 return ret;
 288
 289         if (ret && mei_hbuf_acquire(dev)) {
 290                 ret = 0;
 291                 if (cb->request_buffer.size > mei_hbuf_max_len(dev)) {
 292                         mei_hdr.length = mei_hbuf_max_len(dev);
 293                         mei_hdr.msg_complete = 0;
 294                 } else {
 295                         mei_hdr.length = cb->request_buffer.size;
 296                         mei_hdr.msg_complete = 1;
 297                 }
 298
 299                 mei_hdr.host_addr = cl->host_client_id;
 300                 mei_hdr.me_addr = cl->me_client_id;
 301                 mei_hdr.reserved = 0;
 302                 mei_hdr.internal = 0;
 303                 dev->iamthif_msg_buf_index += mei_hdr.length;
 304                 ret = mei_write_message(dev, &mei_hdr, dev->iamthif_msg_buf);
 305                 if (ret)
 306                         return ret;
 307
 308                 if (mei_hdr.msg_complete) {
 309                         if (mei_cl_flow_ctrl_reduce(cl))
 310                                 return -EIO;
 311                         dev->iamthif_flow_control_pending = true;
 312                         dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
 313                         dev_dbg(dev->dev, "add amthif cb to write waiting list\n");
 314                         dev->iamthif_current_cb = cb;
 315                         dev->iamthif_file_object = cb->file_object;
 316                         list_add_tail(&cb->list, &dev->write_waiting_list.list);
 317                 } else {
 318                         dev_dbg(dev->dev, "message does not complete, so add amthif cb to write list.\n");
 319                         list_add_tail(&cb->list, &dev->write_list.list);
 320                 }
 321         } else {
 322                 list_add_tail(&cb->list, &dev->write_list.list);
 323         }
 324         return 0;
 325 }
 326
 327 /**
 328  * mei_amthif_write - write amthif data to amthif client
 329  *
 330  * @dev: the device structure
 331  * @cb: mei call back struct
 332  *
 333  * Return: 0 on success, <0 on failure.
 334  *
 335  */
 336 int mei_amthif_write(struct mei_device *dev, struct mei_cl_cb *cb)
 337 {
 338         int ret;
 339
 340         if (!dev || !cb)
 341                 return -ENODEV;
 342
 343         ret = mei_io_cb_alloc_resp_buf(cb, dev->iamthif_mtu);
 344         if (ret)
 345                 return ret;
 346
 347         cb->fop_type = MEI_FOP_WRITE;
 348
 349         if (!list_empty(&dev->amthif_cmd_list.list) ||
 350             dev->iamthif_state != MEI_IAMTHIF_IDLE) {
 351                 dev_dbg(dev->dev,
 352                         "amthif state = %d\n", dev->iamthif_state);
 353                 dev_dbg(dev->dev, "AMTHIF: add cb to the wait list\n");
 354                 list_add_tail(&cb->list, &dev->amthif_cmd_list.list);
 355                 return 0;
 356         }
 357         return mei_amthif_send_cmd(dev, cb);
 358 }
 359 /**
 360  * mei_amthif_run_next_cmd - send next amt command from queue
 361  *
 362  * @dev: the device structure
 363  */
 364 void mei_amthif_run_next_cmd(struct mei_device *dev)
 365 {
 366         struct mei_cl_cb *cb;
 367         int ret;
 368
 369         if (!dev)
 370                 return;
 371
 372         dev->iamthif_msg_buf_size = 0;
 373         dev->iamthif_msg_buf_index = 0;
 374         dev->iamthif_canceled = false;
 375         dev->iamthif_ioctl = true;
 376         dev->iamthif_state = MEI_IAMTHIF_IDLE;
 377         dev->iamthif_timer = 0;
 378         dev->iamthif_file_object = NULL;
 379
 380         dev_dbg(dev->dev, "complete amthif cmd_list cb.\n");
 381
 382         cb = list_first_entry_or_null(&dev->amthif_cmd_list.list,
 383                                         typeof(*cb), list);
 384         if (!cb)
 385                 return;
 386         list_del(&cb->list);
 387         ret =  mei_amthif_send_cmd(dev, cb);
 388         if (ret)
 389                 dev_warn(dev->dev, "amthif write failed status = %d\n", ret);
 390 }
 391
 392
 393 unsigned int mei_amthif_poll(struct mei_device *dev,
 394                 struct file *file, poll_table *wait)
 395 {
 396         unsigned int mask = 0;
 397
 398         poll_wait(file, &dev->iamthif_cl.wait, wait);
 399
 400         mutex_lock(&dev->device_lock);
 401         if (!mei_cl_is_connected(&dev->iamthif_cl)) {
 402
 403                 mask = POLLERR;
 404
 405         } else if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE &&
 406                    dev->iamthif_file_object == file) {
 407
 408                 mask |= (POLLIN | POLLRDNORM);
 409                 dev_dbg(dev->dev, "run next amthif cb\n");
 410                 mei_amthif_run_next_cmd(dev);
 411         }
 412         mutex_unlock(&dev->device_lock);
 413
 414         return mask;
 415 }
 416
 417
 418
 419 /**
 420  * mei_amthif_irq_write - write iamthif command in irq thread context.
 421  *
 422  * @cl: private data of the file object.
 423  * @cb: callback block.
 424  * @cmpl_list: complete list.
 425  *
 426  * Return: 0, OK; otherwise, error.
 427  */
 428 int mei_amthif_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
 429                          struct mei_cl_cb *cmpl_list)
 430 {
 431         struct mei_device *dev = cl->dev;
 432         struct mei_msg_hdr mei_hdr;
 433         size_t len = dev->iamthif_msg_buf_size - dev->iamthif_msg_buf_index;
 434         u32 msg_slots = mei_data2slots(len);
 435         int slots;
 436         int rets;
 437
 438         rets = mei_cl_flow_ctrl_creds(cl);
 439         if (rets < 0)
 440                 return rets;
 441
 442         if (rets == 0) {
 443                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
 444                 return 0;
 445         }
 446
 447         mei_hdr.host_addr = cl->host_client_id;
 448         mei_hdr.me_addr = cl->me_client_id;
 449         mei_hdr.reserved = 0;
 450         mei_hdr.internal = 0;
 451
 452         slots = mei_hbuf_empty_slots(dev);
 453
 454         if (slots >= msg_slots) {
 455                 mei_hdr.length = len;
 456                 mei_hdr.msg_complete = 1;
 457         /* Split the message only if we can write the whole host buffer */
 458         } else if (slots == dev->hbuf_depth) {
 459                 msg_slots = slots;
 460                 len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
 461                 mei_hdr.length = len;
 462                 mei_hdr.msg_complete = 0;
 463         } else {
 464                 /* wait for next time the host buffer is empty */
 465                 return 0;
 466         }
 467
 468         dev_dbg(dev->dev, MEI_HDR_FMT,  MEI_HDR_PRM(&mei_hdr));
 469
 470         rets = mei_write_message(dev, &mei_hdr,
 471                         dev->iamthif_msg_buf + dev->iamthif_msg_buf_index);
 472         if (rets) {
 473                 dev->iamthif_state = MEI_IAMTHIF_IDLE;
 474                 cl->status = rets;
 475                 list_del(&cb->list);
 476                 return rets;
 477         }
 478
 479         if (mei_cl_flow_ctrl_reduce(cl))
 480                 return -EIO;
 481
 482         dev->iamthif_msg_buf_index += mei_hdr.length;
 483         cl->status = 0;
 484
 485         if (mei_hdr.msg_complete) {
 486                 dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
 487                 dev->iamthif_flow_control_pending = true;
 488
 489                 /* save iamthif cb sent to amthif client */
 490                 cb->buf_idx = dev->iamthif_msg_buf_index;
 491                 dev->iamthif_current_cb = cb;
 492
 493                 list_move_tail(&cb->list, &dev->write_waiting_list.list);
 494         }
 495
 496
 497         return 0;
 498 }
 499
 500 /**
 501  * mei_amthif_irq_read_msg - read routine after ISR to
 502  *                      handle the read amthif message
 503  *
 504  * @dev: the device structure
 505  * @mei_hdr: header of amthif message
 506  * @complete_list: An instance of our list structure
 507  *
 508  * Return: 0 on success, <0 on failure.
 509  */
 510 int mei_amthif_irq_read_msg(struct mei_device *dev,
 511                             struct mei_msg_hdr *mei_hdr,
 512                             struct mei_cl_cb *complete_list)
 513 {
 514         struct mei_cl_cb *cb;
 515         unsigned char *buffer;
 516
 517         BUG_ON(mei_hdr->me_addr != dev->iamthif_cl.me_client_id);
 518         BUG_ON(dev->iamthif_state != MEI_IAMTHIF_READING);
 519
 520         buffer = dev->iamthif_msg_buf + dev->iamthif_msg_buf_index;
 521         BUG_ON(dev->iamthif_mtu < dev->iamthif_msg_buf_index + mei_hdr->length);
 522
 523         mei_read_slots(dev, buffer, mei_hdr->length);
 524
 525         dev->iamthif_msg_buf_index += mei_hdr->length;
 526
 527         if (!mei_hdr->msg_complete)
 528                 return 0;
 529
 530         dev_dbg(dev->dev, "amthif_message_buffer_index =%d\n",
 531                         mei_hdr->length);
 532
 533         dev_dbg(dev->dev, "completed amthif read.\n ");
 534         if (!dev->iamthif_current_cb)
 535                 return -ENODEV;
 536
 537         cb = dev->iamthif_current_cb;
 538         dev->iamthif_current_cb = NULL;
 539
 540         dev->iamthif_stall_timer = 0;
 541         cb->buf_idx = dev->iamthif_msg_buf_index;
 542         cb->read_time = jiffies;
 543         if (dev->iamthif_ioctl) {
 544                 /* found the iamthif cb */
 545                 dev_dbg(dev->dev, "complete the amthif read cb.\n ");
 546                 dev_dbg(dev->dev, "add the amthif read cb to complete.\n ");
 547                 list_add_tail(&cb->list, &complete_list->list);
 548         }
 549         return 0;
 550 }
 551
 552 /**
 553  * mei_amthif_irq_read - prepares to read amthif data.
 554  *
 555  * @dev: the device structure.
 556  * @slots: free slots.
 557  *
 558  * Return: 0, OK; otherwise, error.
 559  */
 560 int mei_amthif_irq_read(struct mei_device *dev, s32 *slots)
 561 {
 562         u32 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
 563
 564         if (*slots < msg_slots)
 565                 return -EMSGSIZE;
 566
 567         *slots -= msg_slots;
 568
 569         if (mei_hbm_cl_flow_control_req(dev, &dev->iamthif_cl)) {
 570                 dev_dbg(dev->dev, "iamthif flow control failed\n");
 571                 return -EIO;
 572         }
 573
 574         dev_dbg(dev->dev, "iamthif flow control success\n");
 575         dev->iamthif_state = MEI_IAMTHIF_READING;
 576         dev->iamthif_flow_control_pending = false;
 577         dev->iamthif_msg_buf_index = 0;
 578         dev->iamthif_msg_buf_size = 0;
 579         dev->iamthif_stall_timer = MEI_IAMTHIF_STALL_TIMER;
 580         dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
 581         return 0;
 582 }
 583
 584 /**
 585  * mei_amthif_complete - complete amthif callback.
 586  *
 587  * @dev: the device structure.
 588  * @cb: callback block.
 589  */
 590 void mei_amthif_complete(struct mei_device *dev, struct mei_cl_cb *cb)
 591 {
 592         if (dev->iamthif_canceled != 1) {
 593                 dev->iamthif_state = MEI_IAMTHIF_READ_COMPLETE;
 594                 dev->iamthif_stall_timer = 0;
 595                 memcpy(cb->response_buffer.data,
 596                                 dev->iamthif_msg_buf,
 597                                 dev->iamthif_msg_buf_index);
 598                 list_add_tail(&cb->list, &dev->amthif_rd_complete_list.list);
 599                 dev_dbg(dev->dev, "amthif read completed\n");
 600                 dev->iamthif_timer = jiffies;
 601                 dev_dbg(dev->dev, "dev->iamthif_timer = %ld\n",
 602                                 dev->iamthif_timer);
 603         } else {
 604                 mei_amthif_run_next_cmd(dev);
 605         }
 606
 607         dev_dbg(dev->dev, "completing amthif call back.\n");
 608         wake_up_interruptible(&dev->iamthif_cl.wait);
 609 }
 610
 611 /**
 612  * mei_clear_list - removes all callbacks associated with file
 613  *              from mei_cb_list
 614  *
 615  * @dev: device structure.
 616  * @file: file structure
 617  * @mei_cb_list: callbacks list
 618  *
 619  * mei_clear_list is called to clear resources associated with file
 620  * when application calls close function or Ctrl-C was pressed
 621  *
 622  * Return: true if callback removed from the list, false otherwise
 623  */
 624 static bool mei_clear_list(struct mei_device *dev,
 625                 const struct file *file, struct list_head *mei_cb_list)
 626 {
 627         struct mei_cl_cb *cb_pos = NULL;
 628         struct mei_cl_cb *cb_next = NULL;
 629         bool removed = false;
 630
 631         /* list all list member */
 632         list_for_each_entry_safe(cb_pos, cb_next, mei_cb_list, list) {
 633                 /* check if list member associated with a file */
 634                 if (file == cb_pos->file_object) {
 635                         /* remove member from the list */
 636                         list_del(&cb_pos->list);
 637                         /* check if cb equal to current iamthif cb */
 638                         if (dev->iamthif_current_cb == cb_pos) {
 639                                 dev->iamthif_current_cb = NULL;
 640                                 /* send flow control to iamthif client */
 641                                 mei_hbm_cl_flow_control_req(dev,
 642                                                         &dev->iamthif_cl);
 643                         }
 644                         /* free all allocated buffers */
 645                         mei_io_cb_free(cb_pos);
 646                         cb_pos = NULL;
 647                         removed = true;
 648                 }
 649         }
 650         return removed;
 651 }
 652
 653 /**
 654  * mei_clear_lists - removes all callbacks associated with file
 655  *
 656  * @dev: device structure
 657  * @file: file structure
 658  *
 659  * mei_clear_lists is called to clear resources associated with file
 660  * when application calls close function or Ctrl-C was pressed
 661  *
 662  * Return: true if callback removed from the list, false otherwise
 663  */
 664 static bool mei_clear_lists(struct mei_device *dev, struct file *file)
 665 {
 666         bool removed = false;
 667
 668         /* remove callbacks associated with a file */
 669         mei_clear_list(dev, file, &dev->amthif_cmd_list.list);
 670         if (mei_clear_list(dev, file, &dev->amthif_rd_complete_list.list))
 671                 removed = true;
 672
 673         mei_clear_list(dev, file, &dev->ctrl_rd_list.list);
 674
 675         if (mei_clear_list(dev, file, &dev->ctrl_wr_list.list))
 676                 removed = true;
 677
 678         if (mei_clear_list(dev, file, &dev->write_waiting_list.list))
 679                 removed = true;
 680
 681         if (mei_clear_list(dev, file, &dev->write_list.list))
 682                 removed = true;
 683
 684         /* check if iamthif_current_cb not NULL */
 685         if (dev->iamthif_current_cb && !removed) {
 686                 /* check file and iamthif current cb association */
 687                 if (dev->iamthif_current_cb->file_object == file) {
 688                         /* remove cb */
 689                         mei_io_cb_free(dev->iamthif_current_cb);
 690                         dev->iamthif_current_cb = NULL;
 691                         removed = true;
 692                 }
 693         }
 694         return removed;
 695 }
 696
 697 /**
 698 * mei_amthif_release - the release function
 699 *
 700 *  @dev: device structure
 701 *  @file: pointer to file structure
 702 *
 703 *  Return: 0 on success, <0 on error
 704 */
 705 int mei_amthif_release(struct mei_device *dev, struct file *file)
 706 {
 707         if (dev->iamthif_open_count > 0)
 708                 dev->iamthif_open_count--;
 709
 710         if (dev->iamthif_file_object == file &&
 711             dev->iamthif_state != MEI_IAMTHIF_IDLE) {
 712
 713                 dev_dbg(dev->dev, "amthif canceled iamthif state %d\n",
 714                     dev->iamthif_state);
 715                 dev->iamthif_canceled = true;
 716                 if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE) {
 717                         dev_dbg(dev->dev, "run next amthif iamthif cb\n");
 718                         mei_amthif_run_next_cmd(dev);
 719                 }
 720         }
 721
 722         if (mei_clear_lists(dev, file))
 723                 dev->iamthif_state = MEI_IAMTHIF_IDLE;
 724
 725         return 0;
 726 }